Titrating polyelectrolytes  Variational calculations and Monte Carlo simulations
(1996) In Journal of Physical Chemistry 100(1). p.409417 Abstract
Variational methods are used to calculate structural and thermodynamical properties of a titrating polyelectrolyte in a discrete representation. In the variational treatment, the Coulomb potentials are emulated by harmonic repulsive forces between all monomers; the force constants are used as variational parameters. The accuracy of the variational approach is tested against Monte Carlo data. Excellent agreement is obtained for the endtoend separation and the apparent dissociation constant for the unscreened Coulomb chain. The shortrange screened Coulomb potential is more difficult to handle variationally, and its structural features are less well described, although the thermodynamic properties are predicted with the same accuracy as... (More)
Variational methods are used to calculate structural and thermodynamical properties of a titrating polyelectrolyte in a discrete representation. In the variational treatment, the Coulomb potentials are emulated by harmonic repulsive forces between all monomers; the force constants are used as variational parameters. The accuracy of the variational approach is tested against Monte Carlo data. Excellent agreement is obtained for the endtoend separation and the apparent dissociation constant for the unscreened Coulomb chain. The shortrange screened Coulomb potential is more difficult to handle variationally, and its structural features are less well described, although the thermodynamic properties are predicted with the same accuracy as for the unscreened chain. The number of variational parameters is on the order of N^{2}, where N is the number of monomers, and the computational effort scales like N^{3}. In addition, a simplified variational procedure with only two parameters is pursued, based on a rigidrod approximation of the polymer. It gives surprisingly good accuracy for certain physical properties. © 1996 American Chemical Society.
(Less)
 author
 Jönsson, Bo ^{LU} ; Ullner, Magnus; Peterson, Carsten ^{LU} ; Sommelius, Ola ^{LU} and Söderberg, Bo ^{LU}
 organization
 publishing date
 19960104
 type
 Contribution to journal
 publication status
 published
 in
 Journal of Physical Chemistry
 volume
 100
 issue
 1
 pages
 9 pages
 publisher
 The American Chemical Society
 external identifiers

 Scopus:0013080346
 ISSN
 00223654
 language
 English
 LU publication?
 yes
 id
 b7971377b9104cf89d86de1759d40bc4
 date added to LUP
 20161003 19:16:08
 date last changed
 20161010 09:21:23
@misc{b7971377b9104cf89d86de1759d40bc4, abstract = {<p>Variational methods are used to calculate structural and thermodynamical properties of a titrating polyelectrolyte in a discrete representation. In the variational treatment, the Coulomb potentials are emulated by harmonic repulsive forces between all monomers; the force constants are used as variational parameters. The accuracy of the variational approach is tested against Monte Carlo data. Excellent agreement is obtained for the endtoend separation and the apparent dissociation constant for the unscreened Coulomb chain. The shortrange screened Coulomb potential is more difficult to handle variationally, and its structural features are less well described, although the thermodynamic properties are predicted with the same accuracy as for the unscreened chain. The number of variational parameters is on the order of N<sup>2</sup>, where N is the number of monomers, and the computational effort scales like N<sup>3</sup>. In addition, a simplified variational procedure with only two parameters is pursued, based on a rigidrod approximation of the polymer. It gives surprisingly good accuracy for certain physical properties. © 1996 American Chemical Society.</p>}, author = {Jönsson, Bo and Ullner, Magnus and Peterson, Carsten and Sommelius, Ola and Söderberg, Bo}, issn = {00223654}, language = {eng}, month = {01}, number = {1}, pages = {409417}, publisher = {ARRAY(0x90e3688)}, series = {Journal of Physical Chemistry}, title = {Titrating polyelectrolytes  Variational calculations and Monte Carlo simulations}, volume = {100}, year = {1996}, }